Liquid crystalline phases in colloidal suspensions of KNbO nanosheets

Yamaguchi, Daisuke; Miyamoto, Nobuyoshi*; Fujita, Takako*; Nakato, Teruyuki*; Koizumi, Satoshi; Yagi, Naoto*; Ota, Noboru*; Hashimoto, Takeji

Formation of lyotropic liquid crystalline (LC) phase was observed on a charged colloidal platelike particle system yielded from layered niobate crystal of KNbO. Firstly, the effect of mean lateral size (D) of the particle was examined at a constant volume fraction of the particle (.fai.) where a LC phase coexisted with an isotropic (I) phase. The coexisting LC phase was distinctly transformed from nematic to lamellar (L) as D was diminished. Secondly, the .fai. dependence of the interparticle distance (d) was examined along the I-L transition. In the coexistence region, d varied with .fai. and held nearly the same value between I and L phases, apparently deviating from gas-liquid condensation-type phase separation.